In the related art, there has been known an internal combustion engine (engine) having an oil pump for circulating a lubricant (oil) in the internal combustion engine (e.g., see JP 2010-019098 A (Reference 1)).
The internal combustion engine disclosed in Reference 1 has an oil pan which stores a lubricant, an engine sliding part (lubricating part) through which the lubricant in the oil pan is supplied by an oil pump, and a buffer plate which is provided over the entire area of the internal combustion engine so as to receive the lubricant dropping from the engine sliding part and store the lubricant. In addition, it is considered that the oil is supplied to not only the engine sliding part, but also a hydraulic actuating part. Here, when the lubricant mixed with bubbles is supplied to the hydraulic actuating part, a malfunction of the hydraulic actuating part occurs due to the bubbles. In order to inhibit the problem such as the malfunction of the hydraulic actuating part, the internal combustion engine disclosed in Reference 1 is provided with a lubricant bubble removing device including a vibrating body for removing the bubbles included in the lubricant.
Specifically, in the internal combustion engine disclosed in Reference 1, the vibrating body of the lubricant bubble removing device vibrates the buffer plate such that the lubricant received in the buffer plate is vibrated. At this time, the multiple bubbles contained in the lubricant are aggregated by vibration of the lubricant. Therefore, buoyancy acting on the bubbles is increased, and thus the bubbles, which are aggregated on an oil surface of the lubricant in the buffer plate, float to be released outward from the lubricant in the buffer plate.
However, in the lubricant bubble removing device of the internal combustion engine disclosed in Reference 1, the oil in the buffer plate from which the bubbles are separated is supplied to the hydraulic actuating part and the engine sliding part from the oil pan by the oil pump. For this reason, when bubbles are included in the oil supplied from the oil pump due to a change in temperature of the oil or a change in driving state of the oil pump, there occurs a problem in that the oil including the bubbles is supplied to the hydraulic actuating part. For this reason, there is a demand for an oil supply apparatus for a vehicle which is capable of making it difficult for the oil including bubbles to be supplied to the hydraulic actuating part.
Thus, a need exists for an oil supply apparatus for a vehicle which is not susceptible to the drawback mentioned above.